This invention relates to apparatus and methods for covering the rear storage compartment of pickup trucks and similar vehicles. Specifically, the invention relates to a cover apparatus designed to bear and transport a significant top load while maintaining the storage volume of the compartment. In addition, the present invention relates to a covering apparatus with a hinged multiple-panel system for easily accessing all portions of the storage compartment without removing the cover.
Pickup trucks are the most common vehicle designed to include a rear storage compartment. However, other vehicles, including highway vehicles and off-road vehicles such as All-Terrain Vehicles and open trailers, also contain rear storage compartments. Such compartments are composed of two sidewalls or bedrails, an end wall (near the cab or front of the vehicle) and a tailgate which can be lowered or removed to gain access to the contents of the storage compartment or raised to form a rectangular, open topped compartment. Though this compartment, or bed, as it is commonly referred to, is used for the storage of goods, its open top presents many problems for proper storage of valuable, smaller sized items. One of these problems is exposure to the elements. Supplies located in the bed of pickup trucks are completely susceptible to rain, snow, hail, and other environmental conditions. Another problem with the exposed bed is the lack of security provided. With no lid enclosure, goods can easily be removed from the bed, both through unintended load shifting and through theft. Still another negative result of the open topped storage compartment is fuel inefficiency. Air flow restricted by the tailgate portion of the bed causes severe drag resistance on the vehicle's forward motion.
In order to solve these problems and, in some cases, improve the aesthetics of their vehicles, many pickup truck owners put what is generally referred to as a tonneau cover on their truck beds. The basic principle of a tonneau cover is to enclose the open topped storage compartment. This has been accomplished in a number of ways. For example, U.S. Pat. No. 5,207,262 to Rushford (1993) describes a tonneau cover made of a soft fabric material. This material is secured to a track placed on the top portion of the bedrails of the bed by a number of snaps. While the Rushford cover does address the needs of fuel efficiency, element resistance, and removal of goods by unintended load shifting, it does not strongly discourage the removal of stored goods through theft. The fabric nature and snap system of the Rushford-type tonneau covers leaves the cargo stored in the bed at great risk of theft. In addition to this shortfall, fabric covers are susceptible to thermal expansion and retraction that produces a strain on the fabric. Over time, element damage and resulting strain tears the fabric, rendering the fabric cover useless. Furthermore, when the cover is on the truck bed, the hauling capabilities of the truck are limited to the volume underneath the cover, since the fabric cover is not designed to support or transport a top load.
Hard tonneau covers have been designed to address the security issue, but do not adequately address the continuing need for convenient and flexible installation and use. Most hard tonneau covers are fabricated using polyester resins, foam, fiberglass, moldable plastic, metals or a combination of these materials. One such cover can be seen in U.S. Pat. No. 6,340,194 to Muirhead, et al. The Muirhead cover is lockable and hinged to the end of the truck bed closest to the cabin compartment of the truck. Many hard tonneau covers are made in a similar fashion to the one found in the Muirhead patent. These known hard tonneau covers work relatively well in preserving the contents of the truck bed from weather related damage, as well as from theft. Known hard covers, however, have many drawbacks. One drawback is that they almost invariably are designed to rest in or on a track system. This track system often contains many parts and requires time consuming and difficult assembly. The track system usually demands precision installation. This usually means that the truck owner must have his cover professionally installed.
Another major disadvantage to some hard tonneau covers is clearly displayed in U.S. Pat. No. 6,533,344 to Patterson, as well as U.S. Pat. No. 4,313,636 to Deeds. While the Patterson cover is designed to be lockable, and is capable of being hinged and easily removed, the cover displays many characteristic problems. The first of these problems is that the design of the Patterson tonneau cover makes water resistance difficult if not impossible. Another common problem associated with the Patterson and Deeds cover is the requirement of external support members which must be installed to support the cover over the storage compartment. Both covers require an external track or bracing device. The support members are mounted on top of the side walls of the truck bed in the Deeds patent, and on the inside edge of the side walls in the Patterson patent. The Patterson patent describes the use of angle iron as the bracing for the tonneau cover. The bent outside edges of the tonneau cover panel rest on these pieces of angle iron providing some potential lightweight top loading capability. The angle iron and brace system, in addition to reducing the interior volume of the truck bed (up to 25% in the Patterson patent), is connected to the inside edge of the sidewall of the truck bed by bolts that traverse through holes drilled in the truck bed itself. This exemplifies a major problem with many hard top tonneau covers. Drilling holes in the metal portion of the truck bed greatly encourages corrosion of the metal. In addition to this, drilling is often difficult, requiring precision and advanced machinery. Another problem associated with drilling into the truck bed is that most lease agreements prohibit such alterations to the truck.
U.S. Pat. No. 6,109,681 to Edwards, et al. addresses this drilling problem. The solution, as described by Edwards, is a track for hard tonneau covers that is not drilled, but rather clamped onto the truck bed. However, Edwards patent discloses this solution for fiberglass covers that are incapable of carrying an external load. In addition, the Edwards patent utilizes a track mechanism that requires that more parts than just the tonneau cover be purchased, adding to the total cost of the system and the assembly time of the cover.
Another deficiency in the design of known hard tonneau covers is the inability to haul a significant top load. While some manufactures of hard tonneau covers claim that a top load can be supported, they simply mean that the cover can support some incidental weight while the truck is stationary. Due to the material and design of known covers, as well as the lack of any tie down apparatus on most of these covers, no significant top load can be transported on top of the cover. In fact, the only known cover is designed to actually transport any top load. That cover is the Mountain Top Tonneau Cover manufactured by Mountain Top Industries, Inc. The Mountain Top cover is made of aluminum, and is rated to carry up to 220 lbs on top of the cover. This is not a significant load. The cover includes external rails that allow cargo to be strapped down during transportation. The Mountaintop cover, however, also exemplifies numerous deficiencies, for example, the Mountain Top Tonneau Cover requires that holes are drilled into the truck so that bolts can be inserted to support the gas springs of the cover. The result of this requirement is that the cover cannot be used on leased trucks, and also that corrosion of the truck bed is promoted by the drilling of mounting holes. Another problem with the Mountain Top cover, and other known hard tonneau covers, is that the cover consists of one large panel. The cumbersome size and heavy weight of one large panel makes installation, opening, removal, and storage of the cover extremely difficult. The cover panels may weight 200 pounds or more, making them very difficult to handle. Additionally, any time the truck owner wants to haul an object that is higher than the bedrails of the truck, the owner must remove the cover, requiring him to obtain help to remove the large heavy panel and to find a place to store it.
Another problem presented by known single-panel hard tonneau covers is the difficulty in obtaining access to cargo in the portion of the bed nearest the cab since the panel hinge is located on the end of the bed nearest the cab. When the panel is opened, the tailgate end of the bed provides reasonable access, but items in the cab end of the bed must either be retrieved by climbing into the bed, or by squeezing the items through the limited height space between the bedrail and the hinge supports while standing beside the pickup.
Therefore, there is a continuing need for a cover for a vehicle storage compartment that provides the features of: significant top hauling capability; multi-panel design for access to all portions of the bed; simple, trackless, “no drilling required” assembly; and, the ability to remove individual panels quickly and easily. There is a further continuing need for a hard cover that protects the bed contents from the elements, prevents the stored goods from removal by undesired load shifting or theft, improves aerodynamics, and is capable of transporting a significant top cargo load. For purposes of this application, “significant load” is defined as exceeding 220 pounds, up to the rated limit of the pickup truck or vehicle. These rated weight limits vary according to vehicle and can be located on the vehicle's registration. Additionally, there is a continuing need for a cover that allows easy access to all portions of the bed, provides removable panels for easy and quick assembly, installation, removal, disassembly, and storage of the cover, and further requires no external tracks or braces or drilling into the side or end walls of the truck bed.